External illumination apparatus for optical information reading apparatus

ABSTRACT

There is provided an external illumination apparatus capable of increasing flexibility of illumination, the external illumination apparatus including a CPU and a memory so as to control lighting of a plurality of illumination LEDs with reference to a lighting pattern stored in the memory, wherein this lighting control is executed by a lighting command from an optical information reading apparatus.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 13/205,734, filed Aug. 9, 2011, and which claims foreignpriority based on Japanese Patent Application No. 2010-210251, filedSep. 17, 2010, the contents of which is incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an illumination apparatus used in anoptical information reading apparatus for reading optical informationsuch as a bar code and a QR code.

2. Description of the Related Art

Now that traceability is widespread, an optical information readingapparatus is installed in a factory, a physical distribution complex andthe like to decode optical information such as a bar code or an opticalcode given to a product or a commodity. This type of optical informationreading apparatus is called a “bar code reader” or a “code reader”.

The bar code reader irradiates the optical information with laser light,visible light or infrared light to take in reflected light by an opticalreading element (image pickup element). Analysis of information recordedin the optical information is performed from the picked-up image thathas been taken in.

The bar code reader includes illumination LEDs as described in JapaneseUnexamined Patent Publication No. 2008-33465, and takes in the opticalinformation while illuminating a visual field range with theseillumination LEDs. In the case where it is difficult to read the opticalinformation by internal illumination of the bar code reader in somesurface textures and work environments of a work, external illuminationseparate from the bar code reader is used (Japanese Unexamined PatentPublication No. H11-338966).

Although it is generally considered that the bar code reader controlsthe external illumination, the use of the external illumination does notsolve all problems, and delicate control over lighting timing, how tothrow light in the external illumination, light intensity and the likeis often necessary, which limits the control of the externalillumination.

Specifically, it is generally known that capability of the bar codereader to read the optical information largely varies, depending on anirradiation direction of the light to the work. Particularly, whenreading the optical information (the bar code or the QR code) directlyinscribed on the work, which is called direct part marking, even if theoptical information originally has enough inscribing quality to be read,the reading may become unstable, or may be disabled, depending on thedirection at which the light is thrown to the work. From this, anexternal illumination unit capable of partial illumination, which canchange a lighting portion of a plurality of illumination LEDs has beenlaunched. Such an external illumination unit is connected to the barcode reader, and upon receiving a lighting command from this bar codereader, the external illumination unit lights up.

A usage environment of the bar code reader varies depending on the user,and development of the bar code reader has been carried out with this inmind. In the case where the external illumination unit is used, if theexternal illumination unit can perform illumination in as variouslighting patterns as possible, stable reading can be realized to thework requiring fine reading, such as the work subjected to theabove-described direct part marking.

However, in order to realize the various lighting patterns, partialillumination areas in which the illumination LEDs of the externalillumination unit can be arbitrarily controlled so as to be lighted andlighted out need to be increased, and thus, in order to control thelighting and the lighting-out on the basis of each of the increasedpartial illumination areas, a control line corresponding to each of theareas needs to be prepared. This leads to complication of the control,and wiring connecting the bar code reader and the external illuminationunit becomes very complicated.

Obviously, when followability of speeding-up of a production line of afactory where the bar code reader is installed, and an applicable rangeof the bar code reader are intended to be increased, enhancement inflexibility and responsiveness of the control of the externalillumination is sought.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an externalillumination unit capable of realizing various lighting patterns of theexternal illumination unit while simplifying wiring with an opticalinformation reading apparatus.

Another object of the present invention is to provide an externalillumination unit capable of enhancing responsiveness of control ofexternal illumination to thereby increase reading accuracy of theoptical information reading apparatus.

According to the present invention, the above-described technical objectcan be achieved by providing an external illumination apparatus for anoptical information reading apparatus, which is used together with theoptical information reading apparatus having a communication functionwith external equipment, the external illumination apparatus including:a plurality of illumination LEDs; a switching device that switcheslighting and lighting-out on a basis of each area resulting fromdividing the plurality of illumination LEDs into a predeterminedplurality of areas; a memory storing a lighting pattern defining thearea to be lighted; a control device that controls the switching deviceso as to light the illumination LEDs in the area corresponding to thelighting pattern, with reference to the lighting pattern stored in thememory; and an LED driving device that lights the illumination LEDspermitted to be lighted by the control device, upon receiving anexternal lighting command trigger.

Referring to FIG. 44, one specific configuration of the presentinvention is an external illumination apparatus 208 used together withan optical information reading apparatus 206 having a communicationfunction 204 with external equipment, the external illuminationapparatus including:

a plurality of illumination LEDs 210;

a processor 214 as a control device that controls lighting of theillumination LEDs 210 through communication 212 with the opticalinformation reading apparatus 206;

a memory 216 storing a lighting pattern of the illumination LEDs 210;and

an LED driver 218 that drives the illumination LEDs 210, wherein

when a lighting command trigger from the optical information readingapparatus 206 is received, the lighting of the plurality of illuminationLEDs 210 is controlled with reference to the lighting pattern stored inthe memory 216 of the external illumination apparatus 208.

A common lighting pattern is stored in the memory 216 of the externalillumination apparatus 208 and a memory 202 of the optical informationreading apparatus 206. This lighting pattern is set by the user inadvance. In the memory 216 of the external illumination apparatus 208and the memory 202 of the optical information reading apparatus 206,model information of the external illumination apparatus 208 ispreferably stored, by which setting work when the external illuminationapparatus 208 is connected to the optical information reading apparatus206 can be automatized.

Preparing a plurality of lighting patterns as the lighting patternenables the illumination of the external illumination apparatus 208 tobe controlled in the plurality of lighting patterns.

According to the present invention, since the external illuminationapparatus 208 includes the processor 214 as the control device thatcontrols the lighting of the illumination LEDs 210 by the communication212 with the optical information reading apparatus 206, and the memory216 storing the lighting pattern of the illumination LEDs 210, thelighting of the plurality of illumination LEDs 210 can be controlled byreceiving the lighting command from the optical information readingapparatus 206. Accordingly, the illumination of the externalillumination apparatus 208 can be controlled under high responsiveness.Moreover, preparing the plurality of lighting patterns enables theillumination of various aspects. Other objects, and operation andeffects in the present invention will be clear from detailed descriptionof an embodiment below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overall configuration diagram of a bar code reader system;

FIG. 2 is a perspective view of a bar code reader, which is an opticalinformation reading apparatus;

FIG. 3 is a view when arrangement of various types of substratesarranged inside the bar code reader is seen from an obliquely frontside;

FIG. 4 is a view related to FIG. 3, wherein the arrangement of thevarious types of substrates arranged inside the bar code reader is seenfrom an obliquely rear side;

FIG. 5 is a view for describing connection wiring relationships of thevarious types of substrates incorporated in the bar code reader;

FIG. 6 is a view for describing arrangement of a chassis incorporated inthe bar code reader, and a main substrate, a power supply substrate, anda sub substrate assembled to the chassis;

FIG. 7 is a view for describing various elements assembled to thechassis;

FIG. 8 is a view when a camera module is seen from an obliquely rearside;

FIG. 9 is a view when the camera module is seen from an obliquely frontside;

FIG. 10 is a conceptual view for describing an internal structure of thecamera module;

FIG. 11 is a view showing relationships between the camera module andthe various types of substrates, wherein the bar code reader iscontained in a main case of the bar code reader in this state;

FIG. 12 is a view showing the relationships between the camera moduleand the various types of substrates as in FIG. 11, wherein as apreferable example, thermally conductive rubbers as heat releasingmembers are placed on the power supply substrate and the main substrate;

FIG. 13 is a view for describing a state where the thermally conductiverubbers abut on the power supply substrate, the main substrate, and themain case in connection with FIG. 12;

FIG. 14 is a view for describing that an LED substrate (internalillumination substrate) is attached to front end surfaces of a pair ofrod-like extended portions extending forward from the main case, andfront ends of the power supply substrate and the main substrate arefixed to the extended portions;

FIG. 15 is an exploded perspective view for describing the main case ofthe bar code reader, and how an open rear end of the main case is closedby a rear case, wherein a connector substrate is fixed to the rear case;

FIG. 16 is a front view of the main case containing incorporated membersillustrated in FIG. 15;

FIG. 17 is a front view of the main case in a state where the cameramodule is removed from FIG. 16;

FIG. 18 is a view for describing a device that adjusts a focal distanceof the camera module fixed to the main case;

FIG. 19 is a view for describing a device that adjusts deviation of anoptical axis of the camera module fixed to the main case;

FIG. 20 is a view showing a state where an external illumination unit isattached to the bar code reader;

FIG. 21 is an exploded perspective view of the external illuminationunit;

FIG. 22 is a perspective view of the LED substrate with LEDs to beincorporated in the external illumination unit;

FIG. 23 is a diagram for describing attachment relationships of twosubstrates assembled to the external illumination unit;

FIG. 24 is a view showing one example of a sealing structure between afront case and the rear case making up an outer case of the externalillumination unit;

FIG. 25 is a view showing another example of the sealing structurebetween the front case and the rear case making up the outer case of theexternal illumination unit;

FIG. 26 is a partial perspective view, wherein an upper end portion of aplate member, which is a tool for assembling the external illuminationunit to the bar code reader, is extracted;

FIG. 27 is a partial perspective view, wherein a portion of the platemember for describing a fastening structure between the plate member andthe bar code reader, is extracted;

FIG. 28 is a view showing a modification of an attachment fittingprovided in the plate member;

FIG. 29 is a cross-sectional view of the attachment fitting illustratedin FIG. 28;

FIG. 30 is a cross-sectional view of a state where a dedicated externalillumination unit having a small diameter is attached to the bar codereader;

FIG. 31 is a cross-sectional view of a state where a dedicated externalillumination unit having a large diameter is attached to the bar codereader;

FIG. 32 is a view for describing that LEDs included in an internalillumination unit, which is a surface light source incorporated in thebar code reader, are divided into a plurality of areas to controllighting on the area basis, and is a front view of the internalillumination unit;

FIG. 33 is a front view of the dedicated external illumination unithaving the large diameter, and is a view for describing that LEDsincluded in this external illumination unit are divided into a pluralityof areas to control lighting on the area basis;

FIG. 34 is a front view of the dedicated external illumination unithaving the small diameter, and is a view for describing that LEDsincluded in this external illumination unit are divided into a pluralityof areas to control lighting on the area basis;

FIG. 35 is a diagram showing one example of an LED drive circuit eachincorporated in the internal illumination unit and the externalillumination unit

FIG. 36 is a system diagram for controlling partial illumination of theinternal illumination unit and the external illumination unit;

FIG. 37 is a diagram showing details of a switch mechanism of the LEDdrive circuit each incorporated in the internal illumination unit andthe external illumination unit;

FIG. 38 is a view for describing a concept of a “block” and a “row”relating to the LED drive of the internal illumination and the externalillumination;

FIG. 39 is an overall system diagram relating to the lighting control ofsetting areas for the partial illumination of the internal illuminationunit and the external illumination unit;

FIG. 40 is a view showing one example of a setting screen for setting alighting pattern, using a personal computer, and showing a displayaspect of the setting screen when the external illumination unit isabsent, wherein the lighting pattern of lighting all the plurality ofLEDs included in the internal illumination unit incorporated in the barcode reader is selected;

FIG. 41 is a view showing one example of the setting screen for settingthe lighting pattern, using the personal computer, and showing a displayaspect of the setting screen when the external illumination unit isabsent as in FIG. 40, wherein the lighting pattern of lighting the twoopposed areas located on an outer circumferential side among theplurality of LEDs included in the internal illumination unitincorporated in the bar code reader is selected;

FIG. 42 is a view showing one example of the setting screen for settingthe lighting pattern, using the personal computer, and showing a displayaspect of the setting screen when the external illumination unit havingthe small diameter is connected to the bar code reader, wherein thelighting pattern of lighting all the plurality of LEDs included in theexternal illumination unit having the small diameter is selected;

FIG. 43 is a view showing one example of the setting screen for settingthe lighting pattern, using the personal computer, and showing a displayaspect of the setting screen when the external illumination unit havingthe large diameter is connected to the bar code reader, wherein thelighting pattern of lighting all the plurality of LEDs included in theexternal illumination unit having the large diameter is selected; and

FIG. 44 is a conceptual configuration diagram of a typical specificexample of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Embodiment

Hereinafter, a preferred embodiment of the present invention will bedescribed based on the accompanying drawings.

Bar Code Reader System (FIG. 1):

FIG. 1 is a diagram for describing an outline of a bar code readersystem. Referring to FIG. 1, a bar code reader system 1 has a bar codereader 2, which is a two-dimensional information reading apparatus, anda personal computer 3 connected to the bar code reader 2 as needed, andmakes various settings using the personal computer 3 while checking, onthe personal computer 3, an image picked up by the bar code reader 2. Inthe bar code reader system 1, a ring-type external illumination unit 4is further connected to the bar code reader 2 as needed to illuminate awork together with an internal illumination unit 5 of the bar codereader 2, or only by the external illumination unit 4 with operation ofthe internal illumination unit 5 stopped.

The ring-type external illumination unit 4 is a dedicated member for thebar code reader system 1. It is preferable to prepare a plurality ofdifferent types of external illumination units 4. Obviously, anillumination unit other than the dedicated member can be incorporated asthe external illumination unit 4. The “optical information readingapparatus” is generally called a “bar code reader” or a “code reader”,and herein, an industry term, the “bar code reader” is used.

The bar code reader system 1 is installed in a conveyance path ofproducts or goods in a factory where the products or goods on whichoptical information or an optical code such as barcode or QR code isprinted or inscribed are manufactured, so that information recorded inthe optical information printed on the products or goods is read by thebar code reader 2, and this information is transferred to the personalcomputer 3 to analyze the information.

In an example shown in the figure, as disclosed in FIG. 1, a settingprogram is installed on the personal computer 3, by which using thepersonal computer 3, various settings of the bar code reader system 1are made. Obviously, the bar code reader 2 may be provided, for example,with a display device with a touch panel to enable setting work of thebar code reader 2, the internal illumination unit 5 (FIG. 3), and/or theexternal illumination unit 4 (FIGS. 20 and 21), using this displaydevice.

Bar Code Reader 2 (FIGS. 2 to 19):

FIG. 2 is a perspective view showing an appearance of the bar codereader 2. The bar code reader 2 has a main case 6 having a polygonalcross-sectional shape, and a cylindrical front case 7 fixed to a frontend of the main case 6, and the foregoing internal illumination unit 5is incorporated in the cylindrical front case 7. The main case 6preferably has a substantially square cross-sectional shape, as seenfrom FIG. 2 and the like.

A plurality of substrates independent from one another are incorporatedin the bar code reader 2. Referring to FIGS. 3 to 5, the plurality ofsubstrates included in the bar code reader 2 are as follows.

(1) Main Substrate 10:

In a main substrate 10, a CPU and a memory M are mounted to transfer animage to the memory M and process the image in a DSP (Digital SignalProcessor). The bar code reader 2 including the internal illuminationunit 5 is controlled by the CPU of the main substrate 10, andcommunication with the external illumination unit 4 is executed.

(2) Power Supply Substrate 11:

A power supply of the bar code reader 2 is generated. An insulated inputand output circuit is installed.

(3) Sub Substrate 12:

A large-capacity memory is mounted and an acquired image and varioussettings are stored in this large-capacity memory. On this substrate,elements that cannot be mounted on the main substrate 10 with a limitedsize and shape are mounted.

(4) CMOS Substrate 13 (Light-Receiving Substrate):

A CMOS image sensor (optical reading element) is installed, so that theimage is acquired and transferred to the main substrate 10. LEDs 40 forpointer (FIG. 10) are mounted.

(5) LED Substrate 14:

An LED substrate 14 is a disc-like substrate with a circular opening 14a making up the internal illumination unit 5. A plurality ofillumination LEDs 80 are installed on the LED substrate 14 (FIG. 32described later), so that lighting control of the illumination LEDs 80is executed. The plurality of illumination LEDs 80 are arrayed on aplurality of concentric circles with different diameters centering on anoptical axis of a later-described lens assembly 36 of the bar codereader 2. The plurality of illumination LEDs 80 installed in theinternal illumination unit 5 (in the LED substrate 14) are subjected tothe light control by being divided into areas as will be describedlater. In the LED substrate 14, constant current circuits that supply aconstant current to the plurality of illumination LEDs belonging to therespective areas are provided.

(6) Connector Substrate 15:

A connector substrate 15 is a substrate making up an interface of inputand output with respect to an external power supply, an 10, an RS232C,Ethernet (registered trademark), and the external illumination unit 4.Power is supplied to the external illumination unit 4 from the powersupply substrate 11.

Referring to FIGS. 3 and 4, the main substrate 10 and the power supplysubstrate 11 are arranged in opposition to each other, and in a regionsandwiched by respective side edges of the main substrate 10 and thepower supply substrate 11, the sub substrate 12 is provided orthogonallyto the main substrate 10 and the power supply substrate 11. Anarrangement position of the sub substrate 12 and the main substrate 10may be exchanged. The main substrate 10, the power supply substrate 11,and the sub substrate 12 are disposed adjacent to three side surfaces offour side surfaces of the main case 6 having a rectangular cross sectionin the bar code reader 2, and along the respective three side surfaces.The CMOS substrate 13 is located in a space surrounded by the mainsubstrate 10, the power supply substrate 11 and the sub substrate 12,and the CMOS substrate 13 is disposed on one vertical surface orthogonalto the respective substrates 10 to 12. The LED substrate 14 and theconnector substrate 15 are positioned parallel to the CMOS substrate 13so as to be opposed to each other with the CMOS substrate 13 interposedtherebetween.

FIG. 5 is a view for describing connection relationships of thesubstrates 10 to 15. The main substrate 10 is connected to the powersupply substrate 11 through a first FFC 20 (Flexible Flat Cable) and tothe sub substrate 12 through a second FFC 21, to the CMOS substrate 13through an FPC (Flexible Printed Circuit) 22, to the LED substrate 14 ofthe internal illumination unit 5 through a third FFC 23, and to theconnector substrate 15 through a first harness 24. The power supplysubstrate 11 is also connected to the LED substrate 14 of the internalillumination unit 5 through a second harness 25, so that the powersupply to cause the illumination LEDs installed in the LED substrate 14to emit light is supplied from the power supply substrate 11 to the LEDsubstrate 14. The power supply substrate 11 and the connector substrate15 are connected through two harnesses 26, 27 and an FFC 28.

Referring again to FIG. 5, it should be noted that the main substrate 10and the power supply substrate 11 have substantially the same size andshape. In other words, the main substrate 10 is designed to havesubstantially the same size and shape as the power supply substrate 11,and electronic components that cannot be mounted on the main substrate10 because of these limitations are mounted on the sub substrate 12.

Referring to FIGS. 6 and 7, the main substrate 10, the power supplysubstrate 11, the sub substrate 12, and the CMOS substrate 13 areassembled to a chassis 30, which is a resin molded article. As best seenin FIG. 7, the chassis 30 has a box shape having a substantially squarecross-sectional shape, which is an almost similar shape to thecross-sectional shape of the main case 6, and has a form in which oneside surface 30 a of this box shape is closed and the other fivesurfaces are open. The main substrate 10, the power supply substrate 11,and the sub substrate 12 are disposed on three open side surfaces 10 bto 10 d, respectively. The chassis 30 of the resin molded article isopen at the front and rear thereof, and a camera module 32 is insertedfrom a one-end opening 30 f (FIG. 7). The main substrate 10, the powersupply substrate 11, and the sub substrate 12 are located around thecamera module 32 inserted into the chassis 30, which brings a statewhere the camera module 32 is encompassed by the main substrate 10, thepower supply substrate 11, and the sub substrate 12.

Referring to FIGS. 8 and 9, the camera module 32 has a camera holder 35made of a die casting material such as aluminum, and the camera holder35 has a holder body 35 a having a rectangular cross section, a pair ofarms 35 b extending forward and parallel to each other from sidesurfaces of the holder body 35 a opposed to each other, and a pair ofattachment portions 35 c extending from front ends of the pair of arms35 b in directions away from each other. The CMOS substrate 13 is fixedto a rear end surface opening rearward of the holder body 35 a by aplurality of screws 37 (FIG. 8).

For positioning of the main substrate 10 and the power supply substrate11, six claws 38 are integrally formed in the chassis 30 (FIG. 7), andusing these six claws 38, the main substrate 10 and the power supplysubstrate 11 opposed to the same are positioned on two open sidesurfaces 30 b, 30 d of the chassis 30 opposed to each other,respectively. Cut-outs 10 a to receive the claws 38 are formed in themain substrate 10 (FIG. 7). Cut-outs 11 a are similarly formed in thepower supply substrate 11 (FIG. 3). Referring to FIG. 7, the rectangularsub substrate 12 has a pair of through-holes 12 a, 12 b at diagonallyopposite corner portions, and a pair of through-holes 30 g (one of thethrough-hole does not appear in the drawing for a drawing reason) isformed in the chassis 30 corresponding to the pair of through-holes 12a, 12 b. These through-holes 12 a, 12 b, and 30 g are matched, whichallows the sub substrate 12 to be mounted on the chassis 30 by thescrews.

Arrangement of LEDs for Pointer (FIG. 10):

The camera module 32 has the cylindrical lens assembly 36, and the lensassembly 36 is disposed between the pair of arms 35 b, 35 b of thecamera holder 35. Referring to FIG. 10, the CMOS substrate 13 is fixedto a rear-end opening of the holder body 35 a, using the screws 37 (FIG.8). A pair of LEDs 40, 40 for pointer is mounted on the CMOS substrate13. In connection with the LEDs 40 for pointer, diffusion sheets 41 aredisposed immediately in front of the respective LEDs 40 for pointer inthe holder body 35 a. Light of the two LEDs 40 for pointer is radiatedforward through the diffusion sheets 41 and the lens assembly 36, andpoints to two points at a distance from each other within a visual fieldrange of the bar code reader 2. Reference numeral 43 in FIG. 10 denotesa CMOS image sensor which is an optical reading element, and the opticalreading element 43 is installed in the CMOS substrate 13.

The LEDs 40 for pointer are incorporated in the camera module 32, whichmakes it easy to keep a relational position between the optical readingelement 43 and the LEDs 40 for pointer constant, and to downsize the barcode reader 2. Particularly, the LEDs 40 for pointer share the lensassembly body 36 of the bar code reader 2 with the optical readingelement 43, which makes it easy to downsize the bar code reader 2because dedicated lenses for the LEDs 40 for pointer become unnecessary.

The camera module 32 is characterized in that a distance between theoptical reading element (image pickup element) 43 and the lens assembly36 is very large as compared with a case in the related art, and that inthe optical information such as the bar code and the QR code, even anultramicro region thereof can be read with a high resolution. When thecamera module 32 larger in length dimension as compared with the relatedart is contained in the bar code reader 2, the above-described substratearrangement should be noted. That is, introducing the technical idea ofsurrounding the camera module 32 by the main substrate 10, the powersupply substrate 11 and the sub substrate 12 enables the long cameramodule 32 to be contained in the outer case while downsizing the barcode reader 2.

Specifications of the camera module 32 are as follows.

(1) Optical magnification: 0.6 to 1.0 fold (in the embodiment, 0.823fold)

(2) Visual field range: 7.5 mm×4.8 mm to 4.5 mm×2.9 mm (in theembodiment, 5.5 mm×3.5 mm)

(3) Distance from the optical reading element to the lens at a fore-end:35 mm or more (in the embodiment, 40 mm)

FIG. 11 is a perspective view of an assembly in which the substrates 10,11, 12 and the camera module 32 are assembled to the chassis 30. FIG. 12shows a state where thermally conductive rubbers 45 are respectivelyplaced on the main substrate 10 and the power supply substrate 11 asheat releasing members having cushion properties and excellent thermalconductivity. If the heat release properties of the bar code reader 2are required, the assembly is contained in the main case 6 (FIG. 2)having the rectangular cross section with the thermally conductiverubbers 45 attached in the aspect illustrated in FIG. 12 (FIG. 13).

The main substrate 10 and the power supply substrate 11 are arrangedadjacent to, and along the different side surfaces of the main case 6having the polygonal cross section and made of a metal materialexcellent in thermal conductivity, which makes it easy to release heatof the main substrate 10 and the power supply substrate 11 outside, andenables the camera modules 32 to be contained in the space surrounded bythe main substrate 10 and the power source substrate 11, therebyenabling the further downsizing of the bar code reader 2. Particularly,interposing the heat releasing members such as the thermally conductiverubbers 45 between the main substrate 10 and the main case 6, andbetween the power substrate 11 and the main case 6, can increase heatrelease efficiency, and can further downsize the bar code reader 2 fromthis view point.

Reference numeral 46 in FIGS. 13 and 15 denotes a rear case, which isdetachably attached to a rear-end opening of the main case 6 to closethe main case 6. The connector substrate 15 is attached to the rear case46 and the connector substrate 15 is fixed to the rear case 46 usingscrews 47 (FIG. 15). For example, the main case 6, the front case 7, andthe rear case 46 making up the outer case of the bar code reader 2 ispreferably made of a metal material excellent in thermal conductivity,for example, a thermally conductive material such as aluminum.

Referring to FIG. 6, the main substrate 10 and the power sourcesubstrate 11 have through-holes 50, 51 in front-end narrow-widthportions, respectively. The main case 6 of the bar code reader 2 has apair of rod-like extended portions 6 a, which extend parallel to eachother and forward to an inside of the cylindrical front case 7 (FIG.15).

Referring to FIG. 14 in which a front end portion of the main case 6 isextracted, through-holes 52, 53 related to the through-holes 50, 51 ofthe front-end narrow-width portions of the main substrate 10 and thepower supply substrate 11 are formed in the pair of extended portions 6a of the main case 6, and using screws 54 inserted into thesethrough-holes 52, 53, the main substrate 10 and the power supplysubstrate 11 are fixed to the main case 6 (the extended portions 6 a).This allows each of the main substrate 10 and the power supply substrate11 positioned by the three claws 38 of the chassis 30 to be fixed toeach of the extended portions 6 a extending forward of the main case 6by one of the screws 54. In other words, the chassis 30 is fixed to themain case 6 by the total of two screws 54. In order to facilitate workof tightening the screws 54 and work of removing the screws 54, nuts 55into which the screws 54 are screwed are preferably installed at thethrough-hole 50 of the main substrate 10 and the through-hole 51 of thepower supply substrate 11. To the pair of rod-like extended portions 6 aof the main case 6 is fixed the ring-shaped LED substrate 14 at afront-end surface thereof by screws 60. The ring-shaped LED substrate 14is arranged around the lens assembly 36, and the plurality ofillumination LEDs 80 mounted on the LED substrate 14 form a ring-shapedsurface light source located on the outer circumferential side of thelens assembly 36.

FIG. 17 is a view when the main case 6 is seen from the front side. Themain case 6 has a pair of right and left attachment seats 62 in thefront-end surface thereof, and the camera module 32 is fixed to the maincase 6, using this pair of attachment seats 62. FIG. 16 is a front viewof the main case 6 with the camera module 32 incorporated therein. FIG.17 is a front view of the main case 6 illustrated in a state where thecamera module 32 is removed.

Fixing the camera module 32 to the main case 6, which is a metal moldedarticle, can increase positioning accuracy of the camera module 32,thereby increasing positioning accuracy of the visual field range, ascompared with a case where the camera module 32 is fixed to the chassis30.

Since there is employed a configuration in which the assembly in whichthe major substrates incorporated in the bar code reader 2, that is, thepower supply substrate 11, the main substrate 10, and the like, and thecamera module 32 including the lens assembly 36 are assembled to thechassis is incorporated in the outer case (main case 6), preparing aplurality of types of camera modules 32 enables a plurality of types ofbar code readers 2 to be provided to a user, using the same outer case.For the different types of camera modules 32, the same power supplysubstrate 11, the main substrate 10, and the like are employed, and thesame outer case is used to manufacture the bar code reader 2.

The pair of right and left attachment portions 35 c of the camera module32 are seated on the pair of right and left attachment seats 62 of themain case 6, and the respective attachment portions 35 c are fixed tothe corresponding attachment seats 62, using four screws 63 (FIG. 16).

Spacers 65 are interposed between the attachment seats 62 of the maincase 6 and the attachment portions 35 c of the camera module 32 (FIG.18). As the spacers 65, preferably, a plurality of types of spacers 65having different thickness dimensions are prepared in advance, or one ormore spacers 65 each having the same thickness dimension may be layeredto adjust variation in focal distance of the bar code reader 2.Moreover, the focal distance of the bar code reader 2 is varied by usingthe plurality of types of spacers 65 having different thicknessdimensions, by which the bar code readers 2 having different focaldistances while sharing the same outer case can be provided to the user.Moreover, by preparing the plurality of types of spacers 65 havingdifferent thickness dimensions, optical axis adjustment of the cameramodule 32 is preferably performed using the spacers 65 having differentthickness dimensions so that an optical axis of the camera module 32 isa proper optical axis (FIG. 19).

Dedicated External Illumination Unit 4 (FIGS. 20 to 31):

FIG. 20 shows a state where the dedicated external illumination unit 4is attached to the bar code reader 2, and reference numeral 70 denotes acable connecting the bar code reader 2 and the external illuminationunit 4. The power of the external illumination unit 4 is supplied fromthe bar code reader 2.

The external illumination unit 4 in a ring outer shape has a circularoutline, and has a circular opening 4 a in its center. The bar codereader 2 is positioned so that the center of the circular opening 4 amatches the optical axis of the lens assembly 36 of the bar code reader2. A stand 71 is prepared to position the bar code reader 2. As will bedescribed in detail later, the stand 71 is made up of a pair of platemembers 72 fixed to a back surface of the external illumination unit 4by bolts, and attachment fittings 73 to fixedly set the bar code reader2 at an arbitrary height position of the plate members 72.

First, a structure of the external illumination unit 4 will be describedwith reference to FIG. 21. FIG. 21 is an exploded perspective view ofthe external illumination unit 4. In the external illumination unit 4,an LED substrate 77 and a circuit substrate 78 are contained in an outercase made up of ring-shaped, cylindrical front case 75 and rear case 76in a layered state with a stack connector 79 (FIG. 21) and first spacers82 (FIG. 23) interposed therebetween.

The plurality of illumination LEDs 80 are installed in the ring-shapedLED substrate 77 having almost the same size as that of a ringcross-sectional shape of the ring-shaped, cylindrical front case 75. Inthe ring-shaped circuit substrate 78 preferably having almost the samesize as the ring-shaped LED substrate 77, a CPU that controls thelighting of the plurality of LEDs 80 mounted on the externalillumination unit 4, and controls communication with the bar code reader2, and a memory M (FIG. 1) is installed in addition to an LED drivecircuit. Referring to FIG. 23, obviously, the LED substrate 77 and thecircuit substrate 78 are electrically connected, and the LED substrate77 and circuit substrate 78 are fixed to each other by the first spacers82, and the LED substrate 77 is fixed to the rear case 76 by secondspacers 81. In other words, the circuit substrate 78 is fixed to therear case 76 via the LED substrate 77.

Particularly, when a Fresnel lens 102 (FIG. 30) described later isemployed in the front case 75, relative positioning between theillumination LEDs 80 of the LED substrate 77 and the front case 75 isimportant. In the example of FIG. 23, since the LED substrate 77 ispositioned with respect to the front case 75 via the rear case 76, thisnot only allows the front case 75 and the LED substrate 77 to berelatively positioned, but also facilitates assembling work of the LEDsubstrate 77 and the circuit substrate 78.

As a first modification, regarding a setting structure of the LEDsubstrate 77 and the circuit substrate 78, instead of interposing theLED substrate 77, the circuit substrate 78 may be directly fixed to therear case 76 via spacers. As a second modification, the circuitsubstrate 78 may be fixed to the rear case 76 via spacers, and the LEDsubstrate 77 may be fixed to the circuit substrate 78 via other spacers.

FIGS. 24 and 25 show the outer case of the external illumination unit 4configured in a form in which the rear case 76 is fitted in a rear-endopening of the ring-shaped, cylindrical front case 75. As shown in FIG.24, an adhesive 85 is applied to a circumferential surface of the rearcase 76 to fit the rear case 76 in the front case 76, or after applyingthe adhesive 85 to the front case 75, the ring-shaped, disc-like rearcase 76 is fitted, or after fitting the rear case 76 in the front case75, a clearance therebetween is filled up with the adhesive 85 or asealant, or the like. With the above methods, the adhesive 85 or thesealant may be interposed in the clearance between the front case 75 andthe rear case 76 to assure the sealing performance of the outer case bythe adhesive 85 or the sealant. In such cases, both the cases 75, 76 maybe fixed using at least one screw 86 as needed.

Referring to FIG. 25, gaskets 87 may be interposed between the frontcase 75 and the rear case 76 to assure the sealing performance by thesegaskets 87.

Positioning Mechanism of Dedicated External Illumination Unit 4 (FIGS.26 to 29):

FIGS. 26 and 27 are detailed views of the stand 71 (FIG. 20). Referringto FIGS. 20 and 26, a pair of rectangular plate members 72 that eachrises from a portion adjacent to the back surface of the externalillumination unit 4 and the central circular opening 4 a extendsparallel to each other in a state opposed to each other in a radialdirection of the central circular opening 4 a.

The plate members 72 each have a guide slit 72 a extending vertically,and at least one sub slit 72 b parallel to this guide slit 72 a.

Each of the attachment fittings 73 has a form of crossing the platemember 72, and having right and left folded-back portions 73 a that isengaged with both side edges of the plate member 72, and further hasspring properties. A screw 74 is preferably attached in a central siteof the attachment fitting 73 so as not to drop.

The screws 74 are screwed into screw holes 89 (FIGS. 15 and 27) of thebar code reader 2 arranged between the pair of plate members 72. The barcode reader 2 includes projected pins 90 that are received by the guideslits 72 a of the plate members 72 (FIGS. 2 and 15). Two projected pins90 are provided in each of side surfaces opposed to each other of themain case 6 of the bar code reader 2, and a line connecting the twoprojected pins 90 is parallel to the optical axis of the bar code reader2. More specifically, two projected pins 90 are provided in each of theside surfaces opposed to each other of the main case 6 having arectangular cross section, and the two projected pins 90 arerespectively arranged at one end portion and the other end portion ofthe side surface of the main case 6. Moreover, the screw hole 89 thatreceives the screw 74 of each of the attachment fitting 73 is formed ata front end portion of the main case 6 (at an end portion on the frontcase 7 side).

The screws 74 of the attachment fittings 73 having spring properties areloosened to position the bar code reader 2 at a desired height of thepair of plate members 72, and then the screws 74 are screwed, therebybringing the attachment fittings 73 into close contact with the platemembers 72, which allows the bar code reader 2 to be fixed to the platemembers 72. In addition, screw holes 92 (FIGS. 2 and 15) may be providedin side surfaces of the bar code reader 2 (e.g., of rear case 46), andsecond screws 93 to be screwed into these screw holes 92 may be used tofasten the plate members 72 and the bar code reader 2 to each other(FIG. 20). The second screws 93 are arranged in the sub slits 72 b ofthe plate members 72. This allows the side surfaces opposed to eachother of the bar code reader 2 to be fixed to the respective platemembers 72 by the two types of screws 74, 93 located at a distance fromeach other in vertical and width directions.

As best seen in FIG. 20, the guide slits 72 a each extend linearly fromone longitudinal end portion to the other longitudinal end portion ofthe plate member 72, and parallel to the optical axis of the bar codereader 2. This allows a height position of the bar code reader 2 to beadjusted while keeping the optical axis of the bar code reader 2constant.

While each of the sub slits 72 b extends parallel to the guide slits 72a, a lower end of the sub slit 72 ends in a middle portion in thelongitudinal direction of the plate member 72. By ending the lower endsof the sub slits 72 b in the middle portions in the height direction ofthe plate members 72 in this manner, the following advantages can beobtained. When the first screws 74 of the attachment fittings 73 and thesecond screws 93 inserted into the sub slits 72 b are both loosened toadjust the height position of the bar code reader 2, due to the springproperties of the attachment fittings 73, the bar code reader 2 isbasically held at the position unless the user moves up and down the barcode reader 2. However, the above-described arrangement can prevent thebar code reader 2 from being largely lowered at a moment when the userloses hold of the bar code reader 2 for some reason, thereby damagingthe bar code reader 2. This dropping restriction of the bar code reader2 is because of the setting of ending the lower ends of the sub slits 72b at the relatively high position. Further, the second screws 93 screwedinto the bar code reader 2 are locked in the lower ends of the sub slits72 b, which allows the lower ends of the sub slits 72 b to function asstoppers, thereby avoiding excessive dropping of the bar code reader 2.

FIGS. 28 and 29 show attachment fittings 100 as a modification. Each ofthe attachment fittings 100 has a free end portion 101 that extendsupward from a middle portion of the right and left folded-back portions73 a and then turns over to extend downward, and the first screw 74 isattached to this free end portion 101 so as not to drop off through ascrew holder 74 a. According to the attachment fittings 100 of thismodification, even if the first screws 74 completely come off from thebar code reader 2, careless coming-off of the first screws 74 from theattachment fittings 100 can be avoided.

Types of Dedicated External Illumination Unit 4 (FIGS. 30 and 31):

FIGS. 30 and 31 show a state where the external illumination unit 4 isattached to the bar coder reader 2, wherein FIG. 30 shows a first typeof external illumination unit 4A having a small diameter with arelatively small number of LEDs 80, and FIG. 31 shows a second type ofexternal illumination unit 4B having a large diameter with a relativelylarge number of LEDs 80. When the first and second types of externalillumination units 4A, 4B are prepared, the user can use the first andsecond external illumination units 4A, 4B, depending on an environmentwhere the bar code reader system 1 is installed and the like. Modelinformation is stored in the memory M (FIG. 1) of the externalillumination unit 4, and when the external illumination unit 4 isconnected to the bar code reader 2, the bar code reader 2 takes in themodel information stored in the memory M of the external illuminationunit 4 to thereby recognize the external illumination unit 4, whichallows connection setting with the external illumination unit 4 to beexecuted.

The external illumination unit 4A having the small diameter with therelatively small number of illumination LEDs 80 has the Fresnel lens 102at a translucent portion of the front case 75 (FIG. 30), so that thelight of the illumination LEDs 80 mounted on the external illuminationunit 4A having the small diameter can be kept in the visual field rangeof the bar code reader 2 while arranging the illumination LEDs 80 so asto face immediately downward without inclining the illumination LEDs 80.Since the illumination LEDs 80 can be arranged so as to face immediatelydownward, an installation density of the illumination LEDs 80 of theexternal illumination unit 4A having the small diameter can beincreased. In contrast, in the external illumination unit 4B having thelarge diameter with the relatively large number of LEDs 80, therespective illumination LEDs 80 are installed in the LED substrate 77 inan inclined state and directed to the visual field range of the bar codereader 2.

Partial Illumination of Internal Illumination Unit 5 (FIG. 32):

FIG. 32 is a plan view of the LED substrate 14 incorporated in the barcode reader 2. In the ring-shaped LED substrate 14, a large number ofillumination LEDs 80 are arrayed almost uniformly in an entirecircumference thereof. The illumination LEDs 80 are arranged at almostthe same interval on three concentric circles at a distance from oneanother in a radial direction. More particularly, the plurality ofillumination LEDs 80 are arrayed on the plurality of concentric circlesdifferent in diameter centering on the optical axis of the lens assembly36 of the bar code reader 2.

In the ring-shaped LED substrate 14, partial illumination is performed,using, as a unit, each of a total of eight areas that are formed bydividing an entire area into four blocks at even intervals in acircumferential direction, and further dividing each of the blocks intotwo in the radial direction. Specifically, one row in an outermostcircumference is divided into four areas at an interval of 90°. Theseareas are illustrated as an outer circumference first area AEout 1, anouter circumference second area AEout 2, an outer circumference thirdarea AEout 3, and an outer circumference fourth area AEout 4. Twoinnermost and intermediate rows are divided into four areas at aninterval of 90°. These areas are illustrated as an inner circumferencefirst area AEin 1, an inner circumference second area AEin 2, an innercircumference third area AEin 3, and an inner circumference fourth areaAEin 4. The LEDs 80 belonging to the respective areas of AEout 1 toAEout 4, and AEin 1 to AEin 4 are positioned so as to be distributeduniformly in the respective areas.

The illumination can be controlled, using each of the areas of thedivided areas AEout 1 to AEout 4, and AEin 1 to AEin 4 of the internalillumination unit 5 as a unit. The lighting control by the division intothese areas may include control of an amount of luminescence of the LEDs80.

Partial Illumination of External Illumination Unit 4B Having LargeDiameter (FIG. 33):

FIG. 33 is a plan view of the LED substrate 77 of the externalillumination unit 4, and more particularly, shows the LED substrate 77of the external illumination unit 4B having the large diameter. In thering-shaped LED substrate 77, a large number of illumination LEDs 80 arearrayed almost uniformly in an entire circumference thereof. Theillumination LEDs 80 are arranged at almost the same interval on fourconcentric circles at a distance from one another in a radial direction.More specifically, the plurality of illumination LEDs 80 are arrayed onthe four concentric circles different in diameter centering on theoptical axis of the lens assembly 36 of the bar code reader 2.

In the external illumination unit 4B having the large diameter, partialillumination is performed, using, as a unit, each of a total of 32 areasthat are formed by dividing an entire area into eight blocks at evenintervals in a circumferential direction, and further dividing each ofthe blocks into four in the radial direction. Specifically, in thering-shaped LED substrate 77, a row in an outermost circumference isdivided into eight areas at an interval of 45°. These areas areillustrated as an outer circumference first area AEout 1 to an outercircumference eighth area AEout 8. The next row is also divided intoeight areas at an interval of 45°. These areas are illustrated as anouter intermediate first area AEmid 1 to an outer intermediate eightharea AEmid 8. The next row is also divided into eight areas at aninterval of 45°. These areas are illustrated as an outer intermediateninth area AEmid 9 to an outer intermediate 16th area AEmid 16. A row inan innermost circumference is divided into eight areas at an interval of45°. These areas are illustrated as the inner circumference first areaAEin 1 to an inner circumference eighth area AEin 8. The externalillumination unit 4B having the large diameter can also be controlled,using each of a total of 32 areas as a unit. In the externalillumination unit 4B as well, the control of the amount of luminescenceof the LEDs 80 can be executed on the area basis.

Partial Illumination of External Illumination Unit 4A Having SmallDiameter (FIG. 34):

FIG. 34 is a plan view of the LED substrate 77 of the externalillumination unit 4A having the small diameter. In the ring-shaped LEDsubstrate 77, a large number of illumination LEDs 80 are arrayed almostuniformly in an entire circumference thereof. The illumination LEDs 80are arranged at almost the same interval on three concentric circles ata distance from one another in a radial direction. More specifically,the plurality of illumination LEDs 80 are arrayed on the threeconcentric circles different in diameter centering on the optical axisof the lens assembly 36 of the bar code reader 2.

In the ring-shaped LED substrate 77, a row in an outermost circumferenceis divided into eight areas at an interval of 45°. These areas areillustrated as the outer circumference first area AEout 1 to the outercircumference eighth area AEout 8. An intermediate row is also dividedinto eight areas at an interval of 45°. These areas are illustrated asthe outer intermediate first area AEmid 1 to the outer intermediateeighth area AEmid 8. A row in an inner circumference is also dividedinto eight areas at an interval of 45°. These areas are illustrated asthe inner circumference first area AEin 1 to the inner circumferenceeighth area AEin 8. In the external illumination unit 4A having thesmall diameter, the partial illumination can also be set by dividing theentire area into a total of 24 areas. The lighting control by dividingthe entire area into these areas may include the control of an amount ofluminescence of the illumination LEDs 80. A color of the illumination bythe illumination LEDs 80 may be varied, using each of the areas set forthe partial illumination as a unit.

LED Drive Circuit of External Illumination Unit 4 (FIG. 35):

FIG. 35 shows a part of the LED drive circuit. The illustrated LED drivecircuit can light the LEDs 80 on the area basis, and can supply aconstant current to the plurality of illumination LEDs 80 belonging toeach of the areas.

For example, with the small-diameter external illumination unit 4A inFIG. 34, the eight areas resulting from circumferentially dividing thering-shaped LED substrate 77 at the interval of 45° are referred to as“blocks”. For example, the outer circumference first area AEout 1, theintermediate first area AEmid 1, the inner circumferential first areaAEin 1 make up a first block. In each of the blocks, a block switch 105and a constant current circuit 106 are provided. Turning ON the blockswitch 105 brings a state where a voltage can be applied to theplurality of LEDs 80 belonging to the relevant block. For the pluralityof LEDs 80 in each row, a row switch 107 to bypass the LEDs 80 isprovided on the block basis, and a group of the illumination LEDs 80connected parallel to each of the row switches 107 is connected inseries. In FIG. 35, while only one of the illumination LEDs 80 isillustrated in each of the circumferential rows, this is only becausethe diagram is simplified, and it should be understood that a pluralityof illumination LEDs 80 connected parallel to each of the row switches107 are present in series.

The LEDs in each of the rows belonging to each of the blocks areconnected in series, and in each of the rows, the row switch 107 isconnected in parallel.

Accordingly, turning OFF the arbitrary row switch 107 allows theconstant current to be supplied to the plurality of LEDs 80 belonging tothe relevant block and the relevant row. The external illumination unit4A includes this LED drive circuit, by which the area of the partialillumination can be arbitrarily set, using each of the rows in each ofthe blocks as a unit.

Moreover, by providing the constant current circuit 106 in each of theblocks, for example, a current flowing in the illumination LEDs 80 inthe first to third circumferential rows in the same block can bemaintained constant. In other words, without the constant currentcircuit 106, for example, if the illumination LEDs 80 in the firstcircumferential row are switched from OFF to ON when the illuminationLEDs 80 in the second and third circumferential rows are lighted, thevoltage applied to the illumination LEDs 80 in the second and thirdcircumferential rows will change, thereby changing the current flowingthe illumination LEDs 80 in the second and third rows, and thus changingbrightness.

In other words, even when the block switch 105 is turned ON/OFF, theamount of luminescence of the illumination LEDs 80 belonging to theother blocks does not change. This is because the respective blocks areconnected to the power source in parallel. However, when the row switch107 is turned ON/OFF, the number of the LEDs 80 lighted in the relevantblock changes, so that the brightness of the LEDs 80 changes with this.

When the lighting pattern of the partial illumination is set,fluctuation factors of the brightness of the LEDs 80 are desirablyeliminated as much as possible in view of searching an optimal way tothrow the light to the work. For this reason, the constant currentcircuit 106 is provided in each of the blocks. Thereby, when settingwork of the lighting pattern is performed, it becomes easier to find theoptimal lighting pattern by assuring uniformity and constancy of theluminance of the LEDs 80 in the lighted area to perform the partialillumination when the lighting pattern is changed. For the externalillumination unit 4B having the large diameter, and the internalillumination unit 5, the LED drive circuit in FIG. 35 can be similarlyemployed.

Partial Illumination of Internal Illumination Unit 5 and ExternalIllumination Unit 4 (FIG. 36):

The internal illumination unit 5 which is powered from the externalillumination unit 4, and the external illumination unit 4 are bothsurface light sources, and these surface light sources can be eachdivided into several areas circumferentially and radially to performpartial illumination, using each of the areas as a unit, and thelighting pattern indicating which area is to be lighted and which areais not to be lighted can be arbitrarily set by the user. The lightingpattern including the lighting in all the areas can be registered by theuser using the PC 3, and the lighting pattern set by the user is storedin the memory M of the bar code reader 2, and in the memory M of theexternal illumination unit 4 when the external illumination unit 4 isconnected. This lighting control includes the control of the amount ofluminescence of the illumination LEDs 80. In FIG. 36 as well, similarlyto FIG. 35, while only one of the illumination LEDs 80 is illustrated ineach of the circumferential rows, this is only because the diagram issimplified, and it should be understood that a plurality of illuminationLEDs 80 connected parallel to each of the row switches 107 are presentin series.

As described with reference to FIG. 1, the external illumination unit 4includes a control unit of the CPU. Accordingly, as illustrated in FIG.36, the respective block switches 105 and the row switches 107 in therespective circumferential rows are controlled by the CPU of theexternal illumination unit 4, so that when the circumferentially andradially divided partial illumination areas are set, the lightingcontrol of the LEDs 80 is executed, using each of these areas as a unit.

Details of Switch Mechanism (FIG. 37):

FIG. 37 shows details of the block switch 105 and the row switch 107shown in FIGS. 35 and 36. As seen from FIG. 37, for the block switch 105and the row switch 107, transistors 109 are employed as switch elements.In FIG. 37, although the illustration is omitted, it should beunderstood that the constant current circuit 106 is incorporated on theblock basis in the LED drive circuit.

As a modification, a switch can also be provided in each of theplurality of illumination LEDs 80 belonging to each of the blocks, sothat this switch can be controlled to thereby light the LEDs on thebasis of the arbitrary area. As another modification, a current value ofthe constant current circuits 106 may be controlled. Specifically, inaccordance with ON/OFF switchover of the row switches 107, the number ofthe lighted illumination LEDs 80 in each of the blocks changes. When thenumber of the lighted illumination LEDs 80 changes, the overallbrightness of the external illumination unit 4 and the internalillumination unit 5 changes. In order to suppress this change in thebrightness, the control is preferably performed so as to change thecurrent value of the constant current circuits 106 in response to theON/OFF of the row switches 107 so that the overall brightness of theexternal illumination unit 4 and the internal illumination unit 5 iseven. For example, the control may be such that when the row switch 107on the outer circumferential side is turned ON and the row switch 107 onthe inner circumferential side is turned OFF to light out theillumination LEDs 80 on the inner circumferential side, the brightnessof the illumination LEDs 80 on the outer circumferential side isincreased by the original brightness of the lighted-out illuminationLEDs 80 on the inner circumferential side.

As a further modification, in response to not only the ON/OFF switchoverof the row switches 107 but also that of the block switches 105, thecurrent value of the constant current circuits 106 may be changed. Thecontrol of the brightness of the LEDs 80 in response to the switchoverof the block switches 105 may be controlled such that as the number ofthe lighted blocks becomes smaller, the brightness of the lighted LEDs80 is increased, and on the contrary, as the number of the lightedblocks becomes larger, the brightness of the lighted LEDs 80 isdecreased, by which the overall brightness of the external illuminationunit 4 and the internal illumination unit 5 is made even. This controlof the brightness of the lighted LEDs 80 is enabled by changing thecurrent value of the constant current circuits 106, as described above.

Here, it should be noted that in the circuit illustrated in FIGS. 35 and36 of the embodiment, the same constant current circuits 106 areprovided in the respective block circuits, and that the control isperformed so that the value of the current flowing in each of the blocksbecomes a predetermined current value. According to this circuit, locallight and dark, that is, a situation where the LEDs 80 in one of theareas are light and the LEDs 80 in the other area are relatively darkdoes not occur. In addition to this, when the control is performed tovary the brightness in accordance with the number of rows to be lightedor the number of blocks to be lighted, the brightness of all the lightedLEDs 80 is simultaneously changed by the constant current circuits 106,and thus, the brightness in the respective areas is the same.

Lighting Control Areas of the External Illumination Unit 4 and theInternal Illumination Unit 5 (FIGS. 38 and 39):

As described above, the external illumination unit 4 and the internalillumination unit 5 are capable of the partial lighting. Referring toFIGS. 38 and 39, the block switches 105 and the row switches 107 will bedescribed in detail. As seen from FIG. 38, the term “block” means theregion resulting from circumferentially dividing the ring-shaped surfacelight source. Next, the term “row” means the illumination LEDs 80belonging to the common concentric circuit among the illumination LEDs80 belonging to each of the blocks. Accordingly, referring to FIG. 38, afirst row of a first block means a group of the illumination LEDs 80located in the outermost row among the plurality of illumination LEDs 80belonging to “block 1”.

As described above, the power supply to the plurality of illuminationLEDs 80 belonging to each of the blocks is first controlled by the blockswitch 105. On this assumption, the power supply to the plurality ofillumination LEDs 80 belonging to each of the rows is controlled by therow switch 107. Accordingly, the lighting of the LEDs 80 in the firstrow of the first block can be realized by turning ON the row switch 107in the first row on the assumption that the block switch 105 of thefirst block is turned ON.

With regard to the “row”, for example, “row 2” and “row 3” illustratedin FIG. 38 may be treated as one row. That is, the plurality of rowsbelonging to the same block may be treated as one row.

In the partial lighting control described above, for example, setting ofthe second row and the third row of the first block as one partiallighting area can be realized by turning ON both of the two row switches107 in the second row and the third row, on the assumption that theblock switch 105 of the first block is turned ON. Accordingly, asdescribed above, the switches 105, 107 are provided in each of theblocks divided circumferentially, and in each of the rows belonging toeach of the blocks, and the combinations of these enables the partiallighting areas of the external illumination unit 4 and the internalillumination unit 5 to be freely set.

Moreover, as described above, in the drive circuit of the illuminationLEDs 80, the constant current circuit 106 is incorporated in each of theblocks (FIG. 35), and preferably, the constant current circuit 106 isfurther incorporated in each of the rows (FIG. 36). These constantcurrent circuits 106 enable the luminance of the surface light sourcecreated in each of the areas to be kept uniform in the whole of each ofthe areas.

Illumination Control of External Illumination Unit 4 (FIG. 1):

The model information of the external illumination unit 4 is stored inthe memory M of the external illumination unit 4 and the memory M of thebar code reader 2. Moreover, one or more lighting patterns set using thepersonal computer 3 are stored in the memories M of the bar code reader2 and the external illumination unit 4, respectively. Both of the barcode reader 2 and the external illumination unit 4 have the CPUs(processors), and the mutual communication is enabled.

The CPU of the bar code reader 2 determines whether or not the externalillumination unit 4 is a dedicated one capable of communication with thebar code reader 2, based on a connection wiring state between the barcode reader 2 and the external illumination unit 4. Here, the connectionwiring state refers to, for example, pin arrangement of connectionwiring and the like.

When it is determined that the external illumination unit 4 iscommunicable, the personal computer 3 acquires the illumination typeinformation (model information) stored in the memory M of the externalillumination unit 4. After the model information stored in a memory M ofthe personal computer 3 is acquired, the setting program installed inthe personal computer 3 causes a setting screen for setting the partialillumination lighting pattern corresponding to the acquired type of themodel to be displayed on a display of the personal computer 3. Thisallows the user to immediately and easily grasp which lighting patterncan be set for the external illumination unit 4 currently connected.

The illumination setting screens in FIGS. 40 to 43, which have beenprepared in a lighting area setting program in advance, are displayed onthe display of the personal computer (PC) 3. In the illumination settingscreen in FIG. 40, the following settings are enabled, using a mouseconnected to the PC 3. Referring to FIG. 40, the illumination settingscreen includes a ring-shaped image that schematically illustrates theillumination unit, and when a setting item is selected in this screen,the ring-shaped image changes so as to be able to intuitively grasp thislighting pattern.

Items that can be set in the illumination setting screen in FIG. 40 areas follows.

(1) The illumination by the internal illumination unit 5 and theillumination by the external illumination unit 4 can be selectedalternately. When the dedicated external illumination unit 4 is notconnected to the bar code reader 2, as can be seen from the settingscreen in FIG. 40, an item of “use the external illumination” isdisplayed in gray, so this item cannot be selected.

(2) As the lighting areas of the internal illumination unit 5, an “innercircumference” pattern and an “intermediate circumference” pattern canbe selected (FIG. 40). The selection between the “inner circumference”and the “intermediate circumference” may be alternative, or the twopatterns of the “inner circumference” and the “intermediatecircumference” can be selected. The “inner circumference” means thepattern of lighting the inner circumference first area AEin 1 to theinner circumference fourth area AEin 4 in FIG. 32. Selecting only the“inner circumference” means the pattern of lighting the outercircumference second area AEout 2 and the outer circumference fourtharea AEout 4 in FIG. 32. Selecting both the “inner circumference” andthe “inner circumference” means the pattern of lighting the whole area.

Referring to FIG. 40, check marks are placed on both the “innercircumference” and the “inner circumference”, which shows a state wherethe user has selected both the lighting patterns of the “innercircumference” and the “inner circumference”, and the whole area of thering-shaped image is displayed in red. On the other hand, referring toFIG. 41, a check mark is placed on the “inner circumference”, whichshows a state where the user has selected only the “inner circumference”pattern, and only the outer second area AEout 2 and the outercircumference fourth area AEout 4 of the ring-shaped image are displayedin red, while the other areas are displayed in gray, which means thatthey are unselected.

(3) For selection items of the external illumination unit 4, the settingscreen in FIG. 42 is displayed when the external illumination unit 4Ahaving the small diameter (FIG. 34) is connected. On the other hand, thesetting screen in FIG. 43 is displayed when the external illuminationunit 4B having the large diameter (FIG. 33) is connected. When FIG. 42(the setting screen of the small-diameter unit 4A) and FIG. 43 (thesetting screen of the large-diameter unit 4B) are compared, in thesetting screen of the external illumination unit 4A having the smalldiameter (FIG. 42), three patterns of an “inner circumference”, an“intermediate circumference” and an “outer circumference” can beselected, and an “outermost circumference” is displayed in gray, whichmeans that it is in a non-selectable state. In the external illuminationunit 4A having the small diameter, at least one pattern can be selectedfrom the “inner circumference”, the “intermediate circumference” and the“outer circumference”. In contrast, in the setting screen of theexternal illumination unit 4B having the large diameter (FIG. 43), fourpatterns of the “inner circumference”, the “intermediate circumference”,the “outer circumference”, and the “outermost circumference” can beselected. In the external illumination unit 4B having the largediameter, at least one pattern can be selected from the “innercircumference”, the “intermediate circumference”, the “outercircumference”, and the “outermost circumference”.

When the “inner circumference” pattern is selected, all the eight areasof the first area AEin 1 to the eighth area AEin 8 in the innermostcircumference described in the FIGS. 33 and 34 are lighted. When the“intermediate circumference” pattern is selected, in the small-diameterunit 4A, all the eight areas of AEmid 1 to AEmid 8 are lighted (FIG.34), and in the large-diameter unit 4B, all the eight areas of AEmid 9to AEmid 18 are lighted (FIG. 33). When the “outer circumference”pattern is selected, in the small-diameter unit 4A, all the eight areasof AEout 1 to AEout 8 are lighted (FIG. 34), and in the large-diameterunit 4B, all the eight areas of the AEmid 1 to AEmid 8 are lighted (FIG.33). In the large-diameter unit 4B, when the “outermost circumference”is selected, all the eight areas of AEout 1 to AEout 8 in the outermostrow are lighted (FIG. 33).

The setting screen in FIG. 42 is in a state where the selection to lightall the areas of the external illumination unit 4A having the smalldiameter is performed. The setting screen in FIG. 43 is in a state wherethe selection to light all the areas of the external illumination unit4B having the large diameter is performed.

When “close” provided in each of the setting screens in FIGS. 40 to 43is selected, the setting of the lighting pattern ends, and settinginformation of this lighting pattern is transferred to the bar codereader 2, and is transferred to the external illumination unit 4. Thesetting information is stored in the memories M (FIG. 1) of the bar codereader 2 and the external illumination unit 4.

As described above, the external illumination unit 4, storing its ownillumination model information in the memory M, can set the lightingpattern in accordance with the model of the external illumination unit 4by the lighting pattern setting program of the personal computer 3.

Upon receiving a signal of a lighting command from the bar code reader2, the external illumination unit 4 controls the lighting of theillumination LEDs 80 of the external illumination unit 4, based on thesetting information of the lighting pattern stored in the memory M ofthe external illumination unit 4. This control is executed by the CPU ofthe external illumination unit 4.

Obviously, the setting screens in FIGS. 40 to 43 are only examples. Asdescribed above with reference to FIG. 33 (the large-diameterillumination unit 4B) and FIG. 34 (the small-diameter illumination unit4A), a display aspect of the setting screens can also be designed so asto be able to set the lighting and non-lighting for each of the dividedareas. The user may be enabled to arbitrarily modify these settingscreens.

Moreover, the user may register several lighting patterns in advance andbe enabled to make setting, based on the plurality of registeredpatterns. Moreover, the user may set the plurality of lighting patterns,and switch the lighting patterns of the external illumination unit 4,based on a signal from the bar coder reader 2.

In the external illumination unit 4, when the command from the bar codereader 2 is received, the control of the illumination LEDs 80 isexecuted by the CPU of the external illumination unit 4, and referringto the lighting pattern specified by the bar code reader 2 in the memoryM of the external illumination unit 4, the partial illumination of theexternal illumination unit 4 is performed.

In this manner, the external illumination unit 4 with the CPUincorporated therein stores one or more lighting patterns registered inadvance in the memory M provided in the external illumination unit 4,which allows the external illumination unit 4 to execute the one or morelighting patterns only by supplying the lighting command signal from thebar code reader 2 to the external illumination unit 4. Obviously, thiscontrol of the lighting pattern also includes the control of the amountof luminescence of the LEDs 80.

While the bar code reader system 1 of the embodiment has been describedabove in detail, referring to FIG. 44, the conceptual configuration ofthe present invention described above will be simply described asfollows. Referring again to FIG. 44, the setting information of theillumination lighting pattern (including the partial lighting andoverall lighting) set by the personal computer 3 (FIG. 1) is firststored in a memory 202 of an optical information reading apparatus 206.This information is transferred from the optical information readingapparatus 206 to an external illumination unit 208 to be stored in amemory 216 of the external illumination unit 208.

A CPU 214 of the external illumination unit 208 performs the control thelighting portion and the amount of light in accordance withcommunications 204, 212 with a CPU 200 of the optical informationreading apparatus 206, based on the setting information stored in thememory 216 of the external illumination unit 208. The control of thelighting portion is executed by controlling ON/OFF of the foregoingblock switches 105 and the row switches 107 (FIGS. 35 and 36). Moreover,the light amount control is executed by controlling an amount of thecurrent of the foregoing constant current circuits 106 (FIG. 35).

Thereafter, an LED driver 218 of the external illumination unit 208receives an illumination lighting trigger from the optical informationreading apparatus 206, and the ON/OFF switchover of illumination LEDs210 is performed.

As can be understood from the above description, storing the settinginformation of the lighting pattern in the memory 216 of the externalillumination unit 208 enables the complicated lighting pattern of theexternal illumination unit 208 to be executed only with a simple triggersignal. While in the above embodiment, the external illumination unit208 includes the CPU 214, the above-described control of the lightingpattern of the illumination or the like may be executed in a digitalcircuit, instead of the CPU 214.

When the user wants to change the lighting pattern, the user may createarbitrary lighting pattern information, using the illumination settingprogram of the personal computer 3 (FIG. 1), and may similarly cause thelighting pattern information to be stored in the memory 216 of theexternal illumination unit 208. By causing the setting of the lightingpattern to be included in a setting bank, the control of automaticswitchover of this setting bank may be added. The setting bank is a filecollectively storing various parameters of the optical informationreading system, and by preparing the plurality of setting banks inadvance, reading can be executed while automatically switching to theother setting bank, for example, when the reading does not succeed. Inthe case where the reading by the automatic switchover of these settingbanks is performed, the setting information of the lighting patternincluded in each of the setting banks is transferred to the externalillumination unit 208 at timing when the setting bank is switched, andcauses the setting information to be stored in the memory 216 of theexternal illumination unit 208, by which the illumination in thelighting patterns corresponding to each of the setting banks is enabled.

Thus, the present invention is applied to the illumination when theoptical information such as the bar code and the QR code is read.

What is claimed is:
 1. An optical information reading device comprising:an internal illumination unit configured with a plurality ofillumination LEDs; an image sensor that acquires an image; a switchingdevice that switches lighting of the internal illumination unit on oroff for each area resulting from dividing the plurality of illuminationLEDs into a predetermined plurality of areas; a memory storing alighting pattern defining the area to be lighted; a connecting portionconfigured to connect an external illumination unit with the opticalinformation reading device; a control device that controls the switchingdevice so as to light the illumination LEDs in the area corresponding tothe lighting pattern with reference to the lighting pattern and selectsthe internal illumination unit and the external illumination unit to beused.
 2. The optical information reading device according to claim 1,wherein the internal illumination unit is made of a ring-shapedillumination unit, and the plurality of areas are created by dividing awhole area in a circumferential direction and in a radial direction ofthe ring-type internal illumination unit.
 3. The optical informationreading device according to claim 1, wherein the control device furthercontrols the amount of luminescence of the plurality of LEDs of theinternal illumination unit and the external illumination unitindividually.
 4. The optical information reading device according toclaim 1, further comprising: constant current circuits that supplies aconstant current to the plurality of illumination LEDs belonging to therespective area.
 5. The optical information reading device according toclaim 1, wherein the external illumination unit is made of a ring-shapedillumination unit, and has a circular outline, and has a circularopening in its center.
 6. The optical information reading deviceaccording to claim 5, further comprising: a stand that positions theexternal illumination unit to the optical information reading device sothat the center of the circular opening matches the optical axis of theoptical information reading device, wherein the stand has a slit thatallows a height position of the optical information reading device to beadjusted.
 7. An optical information reading system comprising: aninternal illumination unit configured with a plurality of illuminationLEDs; an image sensor that acquires an image; a switching device thatswitches lighting of the internal illumination unit on or off for eacharea resulting from dividing the plurality of illumination LEDs into apredetermined plurality of areas; a memory storing a lighting patterndefining the area to be lighted; an external illumination unitconfigured with a plurality of illumination LEDs; a connecting portionconfigured to connect the external illumination unit with the opticalinformation reading device; a control device that controls the switchingdevice so as to light the illumination LEDs in the area corresponding tothe lighting pattern with reference to the lighting pattern and selectsthe internal illumination unit and the external illumination unit to beused.
 8. An optical information reading system comprising an opticalinformation reading device and an external illumination unit, saidoptical information reading device comprising: an internal illuminationunit configured with a plurality of illumination LEDs; an image sensorthat acquires an image; a switching device that switches lighting of theinternal illumination unit on or off for each area resulting fromdividing the plurality of illumination LEDs into a predeterminedplurality of areas; a memory storing a lighting pattern defining thearea to be lighted; a connecting portion configured to connect anexternal illumination unit with the optical information reading device;a control device that controls the switching device so as to light theillumination LEDs in the area corresponding to the lighting pattern withreference to the lighting pattern and selects the internal illuminationunit and the external illumination unit to be used, and wherein saidoptical information device is connected to said external illuminationunit.